It is conventional to test the possible leakage of a container by firstly introducing into the container a body of fluid under pressure. At the end of a fill time in which the desired quantity of fluid is introduced into the container, the container is closed off. The introduction of the fluid under pressure into the container causes a temperature change of the fluid, and the container is permitted to stand for a preselected period of time to stabilize the pressure thereof by allowing the fluid to attain the temperature of its surrounding.
Following the stabilization period, the pressure of the fluid is measured over a second period of time which, in the conventional fluid testing systems of the past was commonly approximately equal to the stabilization time.
Upon completion of the pressure measurement, the container is vented, allowing the pressure to return to atmospheric.
Where tests are to be made on a number of containers, such as in assembly line operations where the containers are being filled at relatively high rates, it is a desideratum to minimize the total stabilization and test time. One attempted solution to this problem has been to shorten the stabilization time by making an estimation of, and correcting for, a residual stabilization pressure at the end of a shortened stabilization period. This has not proven completely satisfactory because of inaccuracies resulting from the estimates required for the speeded-up testing process and because of part-to-part variations.